Friction draft and buffing gear.



PATRNTRD MAR. 26, 1907.

T. RMRKRRN.

PRIGTION DRAFT AND RUE EING GEAR.

APPLIGATION HLRR sRPT.'7,19o5.

Ia if? AUNITED sTATEs PATENT oEEIoE.

, THOMAS L. MCKEEN, OF EASTON, PENNSYLVANIA.

FnloTloN 4minimi-m4n BUFFING GEAR.

Specification of Letters Patent.

Application med september '1, 190s. sean no. 277.402.

rammed maren 2e, 1907'.

To all whom it may concern: 1 Be it known that I, THOMAS L. MCKEEN, a citizen of the United States, residing at Easton, in the county of Northampton ,and State of Pennsylvania, have invented a new and useful Improvement in Friction Draft and Bufiing Gears, of which the following is a specification. f

This inventin relates more particularly to friction draft and b gears for railwaycars of that type comprising coperatin friction-surfaces, one of which is movable ongitudinall relative to the other under draft and buifirng strains and which are pressed together in a lateral direction by leaf-springs or 'spring-plates to create friction between said lsurfaces. to resist such relative longitudinal movement of the surfaces and cushion the strains orshocks to which the draft and bufling device is subjected.

' While the improvements are especially intended for combined draft and buiiing gears, l they are4 also applicable to other analogous devices, such as 'car-platform buffers and siding-buffers.

The primary object of the invention is to produce a friction draft and'buffing gear enabling the use of flat or straight-leaf-springs Y or platesv as contradistinguished from the bowed or curved springs heretofore employed. Straight or fiatsprings are less expensive to manufacture thanv curved springs, which relquire special bending and tempering appliances. In making the curved springs the --fibers of the metal are strained more or less in springs to always nest or fit one in the other.

perfectly, andv consequently more or less difficulty is experienced in fitting the springs in the s ace provided for them in the draftgear. or such reasons the flat spring-plates are a marked improvement over the curved spring-plates.

Other objects of the invention are to utilize the straight leaf-springs in a friction-gear4 of" com act, strong, and practical construction,

in w 'ch the spring and friction devices are inclosed in a barrel or casing by which they are protected from the weather and from dust and dirt, and to improve friction'draft and buiiing-gears in the respects hereinafter specified, and set forth in the claims.

The fiat s ring-plates can be utilized in draft and bu ng gears havin'g various different arrangements and constructions of the.

parts, and in the drawings several different constructions are illustrated as examples.

In the accompanying drawings, Figure 1 is a horizontal section, partly in plan, of a friction draft and'buiiing gear embodying' my invention and the guides therefor. Fig. 2 is a transverse section thereof in line 2 2, Fig. 1.

Fig; 3 is a similar section inline 3 3, Fig. 1. Fig. 4 is a side elevation thereof, one of the construction.

Like letters of reference refer to like parts in the several figures.

In the construction of the draft and/'buff-Y` rel is provided with lateral projections 62,. which engage rear stops or abutments b3; on-

the guides B to prevent the rearward movel7o cheek-plates being removed. Figs. 5 and 6 are fragmentary views of modified forms of,

ment of the barrelv beyond the position shown l;

in Fig. 1. The draw-bar C of the coupler isi, connected with` the barrel in any suitable95 way-for instance, bythe usual yoke c,- secured to the draw-bar and passing around the rear end of the barrel, so that thebarrel will be drawn forward with the draw-bar by draft on the latter.

D represents'a front end:follower, which passes through the draw-bar yoke and slides 1n the ways of the guides B and normally-1 lbears a ainst front stops or abutments d o n the es, which prevent the forward movement of the follower beyond the position shown in Fig. .1. bar bears against the front follower and pushes the latter rearwardly in bufling. 'The rearward movement of the follower is limited bythe follower striking the front end of the The rear end of the drawf barrel. vThe barrel constitutes in effect and Iis `acts in the same manner as the usual rear or l on opposite sides of a centering-block K, end follower. arranged longitudinally between the front E represents a center or intermediate follower arranged to slide in the central portion i of the barrel. limited by an internal stop or abutment e on the wall of the barrel. The central abutment is preferably so located as to allow about. the same movement of the intermediatefollower that thefront follower has between its abutments and the front end of they lindrical portion of the barrel and bear at opposite ends, respectively, against the rear end of the .barrel and the intermediate follower. The location of the central abutment e is such that the rearward movement of the intermediate follower E will be arrested before the coil-springs are. compressed solid, thereby preventing injury to the springs. The friction devices, which act in conjunction with or supplement the action of the coil-springs F f, are located in the barrel between the front end and intermediate followers and are preferably constructed and arranged as follows:

G represents friction plates or` wedges which move rearwardly with the front follower in bulling, and 1l. represents coperating friction plates or wedges which move forwardly with the barrel under draft on the draw-bar. 'l he friction-plates G will be hereinafter termed "wedges to distinguish them from the other friction-plates H. The wedgesG are oppositely arranged in the barrel and have inclined outer friction-surfaces which bear against cooperating inner friction-surfaces on the friction-plates H. The wedges bear at their outer and inner ends, respectively,against the front and intermediate followers, whereby they and the intermediate follower are pushed rearwardly with the front follower in bulling, and the frictionplates ll bear at their inner and rear ends against internal shoulders i on the barrel, whereby they are drawn forwardly with the barrel and draw-bar. A relative longitudinal movement of the wedges and frictionplates will cause the wedges to move laterally in the barrel on account of their inclined faces bearing against the friction-plates, and

suoli lateral movement of the wedges is op.

posed by leaf-springs or spring-plates I, ar-

ranged longitudinally in. the-barrel between the Vfront and intermediate followers and bearing against the inner sides of the wedgeplates.V 'llie spring-plates are normally flat` orfstraight Vand act by their tendency to rsist lexure to press the wedge-plates forcibly io'utward against. the friction-plates.

ln the preferred construction (shown in lfigs. 1-4) thef-spring-plates are arranged in two sets Its rearward movement is f and intermediate followers. The centeringblock has concaved opposite faces lc or is reduced in thickness between its ends, so that the leaf-springs bear at their ends onl on the eenterin -plate, and the inner faces li of the wedge-p ates are convened, so as to bear oii the springlates only between their ends. As the we( ges bear centrally on the leafsprings, which are supported at their ends, the lateral movement of the wedges will flex or strain the leaf-springs, and the pressure of the wedges on the friction-plates, and consequently the friction between the same, will depend upon the resistance to leXui-e offered by the leaf-springs. This resistance will be lessened or increased with leaf-springs of the same strength acc-erdingly as the springs bear iieaier to or farther from their ends on the thickened ends of the centering-block K, and consequently the capacity of the springs can be'regulated within. .limits by changing the shape cf the centering-block to vary the distance between the beai'irg-points of the sprin gs. The concavity of the faces of the centering-block is preferably somewhat greater than the conveXit-y of the inner faces of the Wedges7 so that the spring-plates can .be bent to the maximum extent without beine' pinched or. clamped between the wedges and gagei'nent of their inclined faces with 'the Wedge-plates and flex the straight leafsprings. The friction between the wedges and friction-plates due to the pressure of the leaf-springs thereon supplements the coilsprings in resisting the longitudinal movement of the draw-bar and barrel, Aand when the Ibarrel'is relieved from draft the coilsprings will restore the parts to normal position. In bufling the barrel and lfrictionplates are held stationary by the engagement of the barrel with the rear abutments on the guides B, while the front follower, wedges, and'intermediate follower are pushed rearwardly by the draw-bar, thereby in a similar manner vcompressing the coil-springs land forcing the Wedges laterally inward against the resistance of the leaf-springs.

The fiat or straight leaf-spring acting to resist the lateral movement of wedges or friction-pieces in a similar manner can be used with various other arrangements and constructions of the parts ol the gear. The

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rigging as 4a whole could be reversed end" for end, so that the barrel would act as the front follower, in which case the so-called front follower would act as the .rear follower. Another reversal would be to make the opposite faces of the centering-block convexed and the cooperating inner faces of the wedges concaved.

Fig. 5 shows aconstruction similar to that described with the exception that the centering-block K is omitted and the bearings for the ends of the leaf-springs I are formed by central lugs or supports l l on the front and intermediate followers D and E', respectively. A

In Fig. 6 is illustrated a draft and bufling gear similar to that described except in the following respects: The leaf-sprin s I2 are all arranged in one set and bear at t eir ends on-the ends of one of the wedges G', which has a concaved inner faceg. AThe other wedge G2 has a convexed inner face g2, which bears centrallyT on the leaf-springs.J The ac.ion of this gear is analogous to the others described; but all of the leaf-springs are flexed in one direction. With this arrangement of the leaf-springs they occu y .less space transversely of the barrel, and) as all of the springs can be flexed by a corresponding movement of the wedges to the same eX- tent as each set of half the number of springs in the other constructions this arran ement gives nearly double the ca acity of t e two set arrangements of the ot er constructions and it also involves fewer parts.

While all of the constructions above described are intended for combined draft and buiing gears, it will be a parent that the described arrangements of).the straight leafsprings and friction-plates could be emp oyed in platform andy siding buffers or other devices intended to resist movement in one direction only.

I claim as my invention` 1. In a friction-gear, the combination of two friction plates or pieces havin coperating friction-surfaces, one of whic plates is movable longitudinally and one of which is moved laterally by the longitudinally-movable plate, and straight leaf-springs which are movable longitudinally with the longitudinally-movable plate and are flexed by and oppose the lateral movement of the laterallymovable. plate, substantially as set forth.

2. In a friction-gear, lthe combination'of two friction plates or pieceswhich have cooperating friction-surfaces'and are .movable longitudinally in opposite directions relative to each other, and one of which is also movable laterally, and straight leaf-s rings which are flexed by and oppose the ateral movement of said laterally-movable plate, substantially as set forth.l

3. In a friction-gear of the character described, the combination of friction-plates lsprings which move lon having coperating inclined friction-surfaces whereby a relative'longitudinal movement of said plates causes a lateral movement of one of the plates in a direction transversely of the direction of said'longitudinal movement, straight leaf-springs which are movable longitudinally and oppose said lateral movement of said friction-plate, and means whereby the lateral movement of said friction-plate flexes said leaf-springs, substantially as set forth. i

4. In a friction-gear of the character described, the combination of friction-plates having coperating inclinedl friction-surfaces whereby a relative longitudinal movement of said friction-plates causes a lateral movement of one of the plates in a direction trans-A versely of the direction of said longitudinal movement, straight leaf-springs which are movable longitudinally and bear between their ends against a part. movable with said llaterally-movable plate, and bearings for the ends of said springs, substantially as set forth.

5'. In a frictiongear of the character de- 'i scribed, the Acombination of a wedge and friction-plate provided with coperatin friction-surfaces, said wedge being movab e longitudinally' of the friction-plate and being caused to move laterally by en agement with said friction-plate, straight lea -springis which are movable longitudinally with sai wedge and oppose the lateral movement thereof,

said wedge bearing a ainst said leaf-s rings or the between their ends o y, and bearingls y as set ends of the leaf-springs, substantia forth.

I o'o 6. In a friction-gear of the character de! `scribed, the combination of a longitudinallymovable wedge having an inclined frictionsurface, a friction-surface against whichthe inclined surface ofthe wed e slides, whereb the Wedge is moved latera y, straight lea itudinally with said springs which move lon wedge and op ose the ateral movement of the Wedge, an means co erating with said wedge and leaf-springs W ereby the lateral movement of the wedge flexesthe leaf-springs', v

substantially as setforth.

7. `In a friction-gear yof the character described, the combination of a longitudinallymovable wedge having an inclined frictionsurface, a friction-surface against which the inclined surface of the. wed e slides, whereb the vwedge is moved latera straight lea 'tudinally with said wedgeand oppose the ateral movement of the wedge, vmeans cooperating with saidwedge and leaf-springs whereby the lateral movement of the wedge flexesthe leaf-sprin s, and one or more springs for restoring t e artis to normal position, substantially as set ort 8. In a friction-gear of theI character described, lthe comblnation of oppositely-arranged longitudinally-movable wedges havscribed, the combination of opposite1y-ar-- ranged longitudinally-movable wedges havmg lnchned outer friction-surfaces and eenvexed lnner faces, friction-surfaces against which the .inclined surfaces of the wedges slide whereby the. wedges are moved laterally toward each other, two sets of straight leaf-springs arranged between said wedges, eaeh set bearing centrally against the convexed face of one wedge, and a centeringblock between said sets of leaf-springs having ends thicker than its central portion against which ends the ends of the leaf-springs bear, substantially as set forth.

Witness my hand this 2d day of Sep-tember, 1905.

THOMAS L. MCKEEN.

Witnesses:

C. W. PARKER, E. C. H URD. 

